66 OBSERVATIONS ON THE BLOOD DISCS. 



of view as if they were animated, which fact will be again alluded to. 

 It was subsequently found, that those discs which had given off these 

 little granules from their interior, disappeared from the field of view, 

 not suddenly bursting, but gradually getting more and more transpa- 

 rent, till no trace whatever of them was to be seen which was attri- 

 buted to the solvent power of the salt and water. 



Having proceeded thus far in his observations on the blood diluted 

 with salt and water, his next endeavour was to prove whether these 

 changes in any way depended upon the saline solution, and whether 

 the same phenomena would occur in blood fresh drawn from the body, 

 having no other fluid for the red discs to float in than its own liquor 

 sanguinis : accordingly, some blood was taken from a small incision in 

 his arm, and placed on a glass, and covered lightly with a thin piece 

 of mica. At first no trace of spinous discs was to be observed ; but 

 after a few minutes they sprang up in all parts of the field of view, but 

 their surfaces were not so much corrugated as when the saline solution 

 was used, neither did the change from the ordinary disc to the spinous 

 one go on so rapidly ; but all the other phenomena were precisely simi- 

 lar to those which took place in the blood treated with salt and water. 



By access to the splendid library of the Royal College of Surgeons, 

 he has been enabled to ascertain what had been done by others ; 

 and it is curious to remark, how beautifully some of the observa- 

 tions of the oldest examiners of the blood can be confirmed and 

 explained by what he has himself witnessed ; and he likewise 

 has found, that many things known and described by them, have 

 been entirely overlooked by writers of modern date. Leuwenhoeck 

 states, that each disc was composed of six smaller ones. Hew- 

 son knew that the discs sometimes assumed a mulberry character, 

 and that the discs of the blood of the eel would sometimes split and 

 allow the nucleus to escape ; but he attributed these changes to putre- 

 faction, and states, that human blood discs will become corrugated, and 

 appear like mulberries when putrid serum is added to them. From this 

 time down to within the last two or three years, these appearances have 

 been nearly overlooked. Professor Schultz must have witnessed the 

 escape of the granules from the red discs, but calls them air bubbles ; 

 he states, that the powerful contraction of the vesicular membrane, 

 excited by the salt and water, caused the elastic fluid contained in the 

 vesicles to be pressed out, and to escape in the form of air-bubbles,- his 

 idea being, that a gas was contained in the interior of the vesicle around 

 the nucleus. It has been stated in the preceding part of this paper, 

 that some of the little granules, after their escape from the parent, 



